The global emergency of tuberculosis: what is the cause?

Abstract

The treatment of tuberculosis is cheap and highly effective, yet worldwide the disease remains a serious cause of illness and death; so serious as to have been declared a ‘global emergency’ in 1993. It is principally a disease of poverty, with 95% of cases and 98% of deaths occurring in developing countries. The incidence of tuberculosis is increasing worldwide, partly due to poverty and inequity and partly to the HIV/AIDS pandemic, which greatly increases the risk of infection proceeding to overt disease. Around 30% of AIDS-related deaths are due to tuberculosis. The emergence of multidrug resistant tuberculosis (MDRTB) is an increasing threat to tuberculosis control. Although treatable with alternative drugs, the cost is enormous and, accordingly, not undertaken in many poor nations. While the overall global incidence of MDRTB is low, it occurs in certain ‘hotspots’ including Russian prisons. Due to adverse socio-economic factors, London has not escaped the general rise in incidence and, without the introduction of active control strategies, there could be a serious epidemic as occurred in New York City ten years ago which required an enormous financial outlay for its control. In view of the global emergency of tuberculosis, the WHO ‘Stop TB’ campaign has called for the universal adoption of its directly observed therapy, short course (DOTS) strategy. Also, through the Massive Effort Against Diseases of Poverty, several international agencies are urging the establishment of effective control programmes worldwide. London should take the lead and set an example.